defrost bypass door orientation on a b body 74' non ac htr box.

[levicah]

I'm hoping someone with a manual can help me. The flap or door that bypasses for defrost can go in 2 or 3 ways, thanks to a 1 screw, triangular bracket. I think I have it correct, but there will be grief if I have to yank the whole box out and start over. I cannot find a exploded assy. diagram on line.
The way it is now, one position seals off both defrost and driver side ducting. When "opened" it allows the majority of air into the defrost, but allows substantial air to also flow into the driver side ducting. does this sound right?